While orthorhombic niobium pentoxide (T-NbO) is one of the most promising energy storage material with rapid lithium ion (Li) intercalation pseudocapacitive response, a key challenge remains the achievement of high-rate charge-transfer reaction when fabricated into thick electrodes. Herein, we report a facile method to create intrinsic defects in T-NbO through a hydrogen (H) reduction, which is effective to overcome the limitations of electrochemical utilization and rate capability. Due to the high number of active sites introduced, the specific capacity of hydrogenated (H-) NbO with oxygen vacancies reaches 649 C g at 0.5 A g, greatly exceeding that of T-NbO which is 580 C g. In addition, theformation of oxygen vacancies leads to increased donor density and enhanced electrical conductivity, which accelerates charge storage kinetics and enables excellent long-term cycling stability (86% retention after 2000 cycles). The analysis of electrochemical impedance spectroscopy (EIS) plots and the calculation of Li diffusion coefficients (D) further explains the high rate-performance of H-NbO. When the electrode thickness increased to 150 μm, the H-NbO still delivers excellent electrochemical properties. Therefore, the introduction of oxygen vacancies provides a new method towards the improvement of the electrochemical properties of various transition metal oxides.
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http://dx.doi.org/10.1016/j.jcis.2019.12.015 | DOI Listing |
Nat Commun
January 2025
Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai, China.
Photocatalytic overall water splitting is a promising approach for a sustainable hydrogen provision using solar energy. For sufficient solar energy utilization, this reaction ought to be operated based on visible-light-active semiconductors, which is very challenging. In this work, an F-expedited nitridation strategy is applied to modify the wide-bandgap semiconductor SrTiO for visible-light-driven photocatalytic overall water splitting.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
Laboratory of Alternative Energy Conversion Systems, Department of Mechanical Engineering, School of Engineering, University of Thessaly, Pedion Areos 38834, Greece. Electronic address:
The coupling of carbon dioxide (CO) with epoxides to produce cyclic carbonates is a desirable decarbonization approach, but its commercial applicability is still restricted by the costly catalysts required, as well as the need for high temperature and high pressure. Herein, oxygen vacancy-rich defective tungsten oxide (WO) rich in Lewis acid sites was modified by Prussian blue (PB), and the obtained composite reaches up to 94 % styrene carbonate yield (171 mmol gh) at ambient temperature and pressure, exhibiting outstanding advantages in the photocatalytic CO cycloaddition reaction compared with currently reported photocatalysts. It is found that the introduction of PB with photothermal properties significantly enhances the capability of WO to absorb and activate CO and epoxide, along with its light utilization ability.
View Article and Find Full Text PDFNano Lett
January 2025
National Innovation Center for Industry-Education Integration of Energy Storage Technology, College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
Rechargeable magnesium ion batteries (RMBs) have drawn extensive attention due to their high theoretical volumetric capacity and low safety hazards. However, divalent Mg ions suffer sluggish mobility in cathodes owing to the high charge density and slow insertion/extraction kinetics. Herein, it is shown that an ultrafast nonequilibrium high-temperature shock (HTS) method with a high heating/quenching rate can instantly introduce oxygen vacancies into the olivine-structured MgFeSiO cathode (MgFeSiO-HTS) in seconds.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Centre de Recherche Scientifique Et Technique en Analyses Physico-Chimiques, CP 42004, Bou-Ismail, Tipaza, Algeria.
ZnO-CoO material was successfully synthesized by the co-precipitation method and used as a catalyst for the removal of diclofenac sodium (DCF). ZnO-CoO exhibited higher catalytic activity in the catalytic process compared to the photocatalytic processes. Under optimum conditions, the activation of peroxymonosulfate (PMS) by ZnO-CoO achieved approximately 99% removal of DCF, confirming the effective adsorption and activation of PMS.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Chemical Engineering, and Guangdong Provincial Key Laboratory of Materials and Technologies for Energy Conversion (MATEC), Guangdong Technion Israel Institute of Technology (GTIIT), Guangdong 515063, China.
Strong metal-support interactions (SMSIs) are essential for optimizing the performance of supported metal catalysts by tuning the metal-oxide interface structures. This study explores the hydrogenation of CO to methanol over Cu-supported catalysts, focusing on the synergistic effects of strong metal-support interaction (SMSI) and oxygen vacancies introduced by the CO treatment to the catalysts on the catalytic performance. Cu nanoparticles were immobilized on Mg-Al layered double oxide (LDO) supports and modified with nitrate ions to promote oxygen vacancy generation.
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